Heat-transmitting support for cooking utensils



K. ILNICKI Oct. 20, 1931.

HEAT TRANSMITTIING SUPPORT FOR COOKING UTENSILSl 1929 2 Shee'os-Shee"v Filed Oct. 30,

Oct. 20, 1931. K. n NlcKl 1327316 HEAT 'VFRANOSMITTING SUPPORT FOR COOKING UTENSILS Filed oct. so, 1929 2 sheets-sheet 2 FIG. 42.

Patented Oct. 20, 1.931

KLEMENS ILNICKI, OF STRYJ', POLAND mr-'rnansmrrme surronr Fon cooxnra tr'rnrrsrns Application led October 80, 1929, Serial No. 403,493, and in Germany September 19, 1929.'I

The present invention relates to heat-transmitting supports and more particularly to a cast iron supporting member for use in cooking apparatus for household purposes.

It is already known to provide Acast iron.

members with insertions of wire, sheet metal, iron plate and similar materials for the purpose of increasing the tensile and bending strength of the .said members. It has like- 1n wise already been. proposed to construct fire bars for boiler and other furnaces in the' interior of which fire bars reinforcing insertions of soft iron are arranged, or which are provided with projecting ribs of wrought iron. .l

It has, however, not hitherto been proposed to provide cast iron supporting members for use in cooking apparatus for household purposes, suc'h as heating plates having cast projections on the underside, or supporting members for such heating plates or yheating grids with' reinforcing insertions, although cast iron members of this kind are,

. l, In view of the rapidly changing temperatures .25 and the stresses to which they are subjected by the placing of kitchen utensils on the cooking apparatus, particularly liably to become cracked. l

There is a known type of cast heating plate v,3o in which reinforcing ribs are employed, the

said reinforcing ribs being of T-shaped cross section and being partially embedded in the fcast'body ofthe plates so that they project therefrom. In this -constructionfwhen sudden for use in acooking apparatus for household y pur oses,sl1ch as, for instance, heating plates wit cast projections on the underside, su portingjmembersv for the latter and gri s,

cooling or heating occurs, `non-uniform stresses arise on the one hand 1n the rlbs and which do not exhibit the above-mentioned drawbacks.

The principal object of the invention is to provide a cast iron supporting member of the kind set forth, comprising in combination: reinforcing ribs, and metal insertions cast into said ribs so as to be entirely enclosed within the latter and having the form of closed eometrical figures, said insertions surroun ing the whole supporting surface and any apertures therein.

In this specification and claims the term closed geometrical figures is intended to mean geometrical figures bounded by straight or curved lines meeting at points, such as regular or irregular polygons, or bounded by continuous curves, such as circles or ellipses.

It' is a further object of the invention to render possible by means of the aforesaid arrangement the construction of light and at the same time strong cast iron members for cooking apparatus, the manufacture of which, by machinery, in large quantities', canl be effected without dilculty, and which meet all the necessary technical requirements 'for 75 casting. purposes and are free from all stresses resulting from casting.' x The provision of insertions having the 'form of'closed geometrical figures, which surround 'anyapertures vin the heating surface, provides a perso feet reinforcement for the said openings.

For the purpose of mass production of the cast iron supporting members, according to the invention, by means of casting machines, -it is advantageous to arrange that the insertions should form an integral unit. The insertions may be bent over at the angular points of the closed geometrical figures, in which case the parts which are bent over may serve as supports in the mould during the casting of the insertion' into the interior of the supporting member.

For the purpose of furtherfacilitating Lhe `casting operation for embedding the insery tions in position, the latter are preferably provided with open ends which are connected y means 'of clamp members, the projecting ends of which likewise serve for supporting the insertion in the mould during the casting operation. This arrangement renders it particularly easy to place the insertions in position and hold them in place in the mould, which constitutes an important feature in the case of mass production.

In the accompanying drawings Fig. 1 is a view from below of an improved cooking i stove top plate section,

is a cross section on line c-d of Fig; 8,

ig. 10 is a cross section on line c-d of Fig. 8,

Fig. 11 is a partial section on line e-f of Fig. 8,

Fig. 12 is a partial cross section on line- Y of Fig: 8, and F ig. .13 is a partial cross section on line j-c of Fig. 8.

Referring Erst to the construction` shown in Figs.` 1, 2, 3 and V'4, the plate l2 is formed neary its periphery and along its middle portion with comparatively strong reinforcing ribs'l having a considerable vertcial dimension. The body of the plate. 2 is comparatively thin, and isv reinforced by the said ribs 1 and additional ribs 3 and 4, the latter being of a smaller vertical dimension than the ribs 1. By suitably choosing the vertical dimension of the ribs 1, 3 and 4 'it is possible to produce a plate which will have a muchv higherresistance to outer forces than a plate of uniform strength made of the same quantity of cast iron. The cross ribs 3 and 4 serve not only for increasing the rigidityof the late but also for .facilitating the casting, masmuch as they form passages through which the cast :iron flows during the casting I operation. The plate is, in addition, provided with peripheral ribs 5, 5 and 6, 6 which may be of the same vertical dimension as the heavier cross ribs 3. The peripheral ribs 5, 6 may be connected to the main ribs 1 by short cross ribs 7 AThe longitudinal ribs 6, 6 are as may be seen from Fig. 4 provided with recesses 8 and 9'which are staggered in adjacent plate sections so that when several sections are assembled theywill overlap at the edges. The plate is provided with opening or holes 10 for the reception of screws or other fastening means for connection to sup' porting bars or beams arranged under the plates,- for instance, beams or rods of the kinds shown in Figs. 5-7 It will be seen that the main reinforcing ribs 1 are arranged to cross near the holes 10 and to surround the latter.

The main ribs 1 are provided with insertions 11 made of wire, flat iron bands, sheet iron, soft iron or other material having a high tensile strength. Insertions preferably constitute a continuous or connected unit, which commences at a point 12 and finishes at an adjacent point 13. At the points of contact of adjacent portions of the iron insertions there are provided connecting clamps 14 the ends of which are alternately bent upwards as at 15 and downwards at at 16. These bentl ends constitute legs or supports by means of which the insertion is held in the casting mould. It will be understood that during vthe casting operation the insertionas a Wholeremains stationary within the casting mould, and becomes entirely embed- `ded in the molten cast iron.

The ribs 1, 3, 4 are all provided upon the under side of the cooking plate and they serve the additional purpose of baflles which to a certain extent hold and guide the flames and hot air currents set up by the fire burning under the plate. It will be understood that these ribs produce eddy currents in the hot air, whereby the heat absorption by the plate is`considerably improved. As on the other hand the plate is-comparatively thin upon a .considerable portion of its surface, the heat will pass easily result being that cooking utensils supported bythe -plate will be rapidly heated. The

through the plate. to the opposite or outer surfacethereof, the' As mentioned above, the reinforcby the considerable difference of the temperatures existing vat the upper andthe lower surfacesof the late.

The above Aescribed improved cooking plates may be supported by beams or carrier rods of the construction shown in Figs. 5, 6 and 7. These beams or carrier rods are likewise made of cast iron and provided with insertions 18 made of soft iron wire. The in. sertion commences at the point 419 runs through the whole length of the beam, around longitudinal holes 2O which latter serve for the reception of connecting screws, and returns to an adjacent point 21. The two thicknesses of the insertion are at suitable points connected and reinforced by clamps 22, the ends of which are alternately bent upwards as at 23 and downwards as at 24. These bent.

Fig. 7, are both formed with horizontal eztprojections.

tensions 25, in order to obtain a particularly -effective support for the insertion at the two ends. .It will be seen from Fig. 6 that the beams are reduced in thickness at the ends 26. The cooking plate to be fixed to beam 17 is indicated in Fig. 7 by the numeral 27. It may be seen from Fig. 7 that one result of the construction of the improved plate, will be the fact that the hot fiames or gases will flow at the point of connection in the direction of 38, whereby rapid heating of the plate will be facilitated.

The improved kitchen grid shown in Figs. 8-13 may be of rectangular or square formation and-is provided at the four corners with diagonal supporting arms 28. The transverse members or rods 29 of the grid are parallel to each other and are separated by air slots. The transverse lmembers 29'are formed upon the under faces with teeth 31 or other These teeth or projections assist the cooling of the grid by cold air coming from underneath. By this means a danger of premature burning of the grid is avoided. The object of the arms 28 is to facilitate the fixing of the grid in the usually somewhat irregular opening of a kitchenv stove made of brick.

The grid is provided with internal insertions made ofsoft iron or other material having a high tensile strength. These insertions commence at the point 34 and they extend along the whole periphery of thev grid and also pass ina zigzag line through the transverse members 29, ending at the point 35. The lwhole insertion may thus be made up of a continuous piece of wire or other suitable material. For the purpose of giving rigidity to the insertion, clamps 36 are provided. In this case the clamps need not be formedv with the projecting leg portions, as the whole of the insertion lies within a plane determined by the projecting arms 28. As

may be seen from Fig. 12 the ends 37 of the insertion are slightly bent upwards for the purpose of obtaining a safe support of the insertion Within the mould and for ensuring a uniform embedding of the insertion within cast iron. j

It may be pointed out that the insertion used in the above described plates, beams and grids may also if desired be made of a mateial other than iron,l for instance, they may e made of suitable alloys having a considerable tensile strength. It is advisable io clean either chemically or mechanically the insertions before placing them in the mould in order to ensure an intimate connection of the insertions with the material of the support. For the same purpose the insertionsmay be covered or coatedwith suitable chemical substances which increase the resistance and strength of the insertions.

I claim:

in cooking apparatus for household purposes, comprising in combination: reinforcing ribs, and metal insertions cast into said ribs so as to be entirely enclosed within the latter and having the form of closed geometrical figures, said insertions surrounding the whole supporting surface and any apertures therein. Y

2. A cast iron supporting member ,for .use in cooking apparatus for household purposes, comprising in combination: reinforcing ribs, and soft iron insertions cast into said ribs so as to be entirely enclosed within the latter and having the form' of closed geometrical figures, said insertions surrounding the whole supporting surface and any apertures there- 1n.

3. A cast iron supporting member for use 'in cooking apparatus for household purposes, comprising in combination: reinforcing ribs, and soft iron wire insertions cast int-o said ribs so as to be entirely enclosed within the latter and having the form of closed geometrical figures, said insertions surrounding the whole supporting surface and any apertures therein.

4. A cast iron supporting member for use in cooking apparatus for household purposes, comprising in combination: reinforcing ribs, and metal insertions cast into said ribs so as to be entirely enclosed within the latter and having the form of closed geometrical figuressaid insertions surrounding the whole supporting surface and any apertures therein and forming an integral unit.

5. A cast iron supporting member for use in cooking apparatus for household purposes, comprising in combination: reinforc ing ribs, and metal insertions cast into said ribs so as to be entirely enclosed within the latter and having the form of closed geometrical figures, said insertions surrounding the whole supporting surface and any aper-` tures therein and being bent over at the angu- 1 lar pointsv of the geometrical figures to form supports for said insertions in the mould during the casting operation.

6. A cast iron supporting member for use in cooking apparatus for household purposes, comprising in combination: reinforcing ribs, and meta-l insertions forming an integral unit cast into said ribs so as to be entirely enclosed Within the latter and having the form of closed geometrical figures,

said insertions surrounding the whole supporting surface and any apertures therein and being bent over at the angular points of the geometrical figures to form supports lfor said insertions in the mould during the ca sting operation.

Signed at Warsaw, Republic of Poland, this fifteenth day of October, 1929.

KLELIENS ILNICKI. 

